Spark-arrester



(No Mode-1.)

C. G. LUTHMAN.

SPARK ARRBSTBR.

No. 477,058. Patented June 14, 1892.

UNITED STATES PATENT OFFICE.

CARL G. LUTHMAN, OF ALTOONA, PENNSYLVANIA.

SPARK-ARRESTER.

SPECIFICATION forming part of Letters Patent No. 477,058, dated June 14,1892.

Application filed February 23, 1892. Serial No. l122,538. (No model.)Patented in Sweden March 26, 1889, No. 2,089, and in Finland October 7,1890, No. 367.

To all whom it may concern:

Beit known that l, CARL G. LUTHMAN, a subject of the King of Sweden, anda resident of Altoona, Blair county, Pennsylvania,

have invented certain Improvements in Spark- Arrcsters, (for which Ihave obtained Letters Patent as follows: in Sweden March 26,1889, No,2,089, and in FinlandOctober 7,1890,No. 367,) of which the following isa specification.

The objectlof my invention is to provide a spark-arrester for stacks,with a view of preventing the escape of sparks or cinders and permittingthe passage of the gases and smoke. This object I attain in the mannermore fully set forth hereinafter, vreference being had to theaccompanying drawings,in whichk Figure l is a sectional view on the linel 2, Fig. 2, of a locomotive-stack provided with a spark-arresterconstructed in accordance with my invention. Fig. 2 is ar plan view ofthe same. Fig. 3 is a sectional view of a modified construction on theline 3 4, Fig. It. Fig. 4 is a sectional plan view on the line 5 6, Fig.3; and Figs. 5, 6, and 7 are vertical sections of further modifications.

Referring to Fig. l, A represents a number of metallic strips curved inhelical form and adapted to the interior of the stack B, the stripsbeing placed at an acute angle to the sides of the stack, so thatpockets @are formed, as illustrated in Fig. 1, and the lower ends of thestrips are placed ina nearly vertical position, in order that the gasesmay meet with comparatively small uresistance when entering the stack;but the length of pitch decreases toward the upper end of the stack, sothat the gases are revolved with increased force as they ascend; but,ifdesired, the pitchof the strips may be equal throughout the length ofthe stack.

Secured within the stack in any suitable manner is a plate C, which maybe made in several different forms. For instance, Fig. l illustrates aplate tapering in Width and twisted in helical form in the samedirection as the direction of twist of the strips A. In Fig. 6 the shapeof the plate is `practically the same, except that it is much shorter inlength, and in Fig. 7 is shown a plate twisted in a such manner as toform a helical cone, which will offer but little resistance to theescape of the gas, but will force the gas and the sparks out toward thesides of the stack and act not only as deflecting-plates, but giving tothe gases a rotary motion, as will be readily understood.

At the top of the stack is an inwardly-projecting flange D, curved orinclined in crosssection, and its inner diameter being about equal tothe inner diameter of the clear passage between the upper portion of thestrips A, and surmounting this iiange there is a ring E of cylindricalform,and within this ring are a number of radial blades F, which arecurved to correspond with the direction of the set of helices A and C,their upper ends, however, merging into a vertical line, so that thegases, which have been given a rotary motion within the stack, will bedischarged in a Vertical line and the soot and crushed particles willnot be discharged by centrifugal force immediately around the stack; or,if desired, the ring E may be dispensed with and the blades F be carriedby the ange D, as illustrated in Fig. 6.

In action the gases entering at the lower end of the stack are forced bythe spirals to adopt a rotary motion, whereby the sparks and cinders arethrown outward by cent1-ifm gal force against the wall of the stack andare there crushed and grounded by being held in the pockets e betweenthe strips A'a'nd the wall of the stack during their ascension. -Thesparks which have not been extinguished or ground before reaching thetop of the stack are forced under the ila-nge D and are there crushed,thus losing their energy, and in falling the crushed particles arecarried away by the ascending gases.

vIn Figs. 3 andll I have illustrated a modification of my invention, inwhich a conc C takes the place of the helical plate C in Fig. l, andbetween this cone and the wall of the stack are a number of curvedplates A which act in the same manner as the strips A to give the gasesand sparks a rotatory motion, and

thus by centrifugal force throw the heaviestl parts outward under theflange D, as before described, the cone preventing the escape of anysparks in a vertical direction and at the saine time offering but littleresistance to the ascending gases.

The devices shown in Figs. l to 4 and Figs.

IOO

G and 7 are particularly applicable to short stacks-such, t'or instance,as those used on locomotives; but where a long stack is to be suppliedwith devices of this class it will be sufficient to make the strips A ofsufficient length to crush the sparks in their upward passage in theangle between the strips A and the wall of the stack, thus making theflange D unnecessary, and the length of stack between the upper end ofthe strips andthe discharge end will give the gases time to assume aVertical motion and pass out in a vertical direction, thus dispensingwith the delectingplates F, as shown in Fig. 5.4

I am aware that helically-arranged defiecting-strips have heretoforebeen employed in stacks, and am also aware thata central plate has beenused to deflect the escaping products of combustion. Hence I do notclaim either of these broadly, but

What I do claim, and desire to secu re by Letters Patent, is

1. The combination, in a spark-arrester, of the stack, a series ofdetlecting strips or plates A, secu red atan angle to the walls of thestack and forming a helix, and a helical deflectingplate centrallymounted within the stack and curved in the same direction as thehelicaldefleeting-strips A, substantially as specified.

2. The combination, in a spark-arrester, of

the stack, a series of strips or plates secured thereto and forming ahelix, the lower ends 3. The combination of the stack, a series ofhelical detlecting-strips, a fiange at the-top of said stack projectinginwardly and forming with the walls of the stack a pocket, into whichthe sparks or cinders are directed, and a series of deflecting-blades ator at about the top of the stack, whereby the escaping gases aredeflected into a vertical path, substantially as specified.

4. The combination, in a spark-arrester, of the stack, a series ofdefiecting strips or plates A, secured at an angle to the walls of thestack and forming a helix,ahelical delecting-plate mounted centrallywithin the stack and curved in the same direction as the helicaldeflecting strips, and a flange at the top of the stack, said fiangeprojecting inwardly and forming with the walls of the stack a pocket,into which thc sparks or cinders are directed, substantially asspecified.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

oARL e. LUTHMN.

Witnesses:

J AooB SNYDER, GUSTAV. BERG.

